http://www.ft.com/cms/s/0/302914bc-40a7-11dd-bd48-0000779fd2ac.html

Facebook, the fast-growing social network, has taken a significant lead over MySpace in visitor numbers for the first time, according to one popular measure of internet traffic.

Facebook attracted more than 123m unique visitors in May, an increase of 162 per cent over the same period last year according to ComScore, a company that monitors websites. That compared with 114.6m unique visitors at MySpace, Facebook’s leading rival, whose traffic grew just 5 per cent during the same period, ComScore said.

The findings mark the first time that Facebook, launched in 2004, has taken a significant lead in unique visitors, after ComScore’s April traffic figures showed the rivals in a virtual tie. They come at a time of change inside Facebook, as the one-time upstart attempts to transform itself into a leading media company. Several members of the original executive team have left the company in recent weeks.

The departures include Adam D’Angelo, chief technology officer and personal confidant of Mark Zuckerberg, the company’s 23-year-old founder and chief executive; and Matt Cohler, Facebook’s first official hire, who was in charge of product development.

Mr Zuckerberg has appointed Sheryl Sandberg as his second-in-command. Ms Sandberg, who helped develop Google’s lucrative advertising business, is expected to play a crucial role in the development of Facebook’s revenue model.

The management changes come as the company is under pressure to justify the $15bn valuation it drew last year in an investment round with Microsoft.

Facebook is a private company and does not disclose official sales or profit figures. But people close to the company have claimed that it made $150m in sales last year. That figure is expected to grow to $300m-$350m this year as it attempts to broaden its revenue stream.

Counting unique visitors is just one way to measure the website popularity. Many sites, including Facebook, measure audience engagement by tracking the number of repeat, or “active” users of their sites, leaving out those who visit a site once and never return. MySpace claims to have about 110m active users, Facebook about 80m.